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It's almost time for one of our favorite winter holidays: Groundhog Day! Where I live (in the United States,) every February 2nd we celebrate a day that's pretty close to the halfway point of winter. And all eyes turn to a little animal called the groundhog!

Probably the most famous groundhog in the United States lives in a little town in Pennsylvania called Punxsutawney, and he's called Punxsutawney Phil. The story goes that when this groundhog comes up from his underground den and sees his shadow, that means there are six weeks of winter left.

Now, there aren't many holidays that are just about animals, so we thought now would be a great time to learn more about Phil and the other members of his family!

Groundhogs, or some people call them, woodchucks, belong to a group of animals called rodents. Other kinds of rodents include squirrels, hamsters, and-- you've got it Squeaks, also rats and mice.

All rodents have sharp front teeth called incisors. You have incisors, too! They're the four front teeth right in the front of your mouth, on the top and the bottom.

Your incisors are often the first teeth you lose as your permanent teeth start to come in, but rodents like the groundhog don't usually lose their incisors. Instead, their front teeth do something else that's pretty cool: they grow and they keep growing longer and longer!

If the groundhog didn't do something to keep its incisors from growing too long, it'd have a pretty hard time eating. So groundhogs, like other rodents, chew or gnaw on things like sticks and trees, This wears their teeth down and keeps them nice and short.

So, if you see a groundhog chewing on wood, it's probably not eating it; it's just filing down its front teeth.

But groundhogs do eat lots of different things! Its diet is mostly plants like grasses, berries, and nuts, but they'll also eat small insects, grubs, and snails if they can find them.

And when they're not out looking for food, groundhogs hide, sleep, and raise their families in long underground tunnels called burrows.

Burrows can be really big! Many of them are about as long as five or six cars parked end-to-end, and every burrow typically has two main rooms. One is used as kind of a living room for sleeping and hanging out in. The other is used only as a bathroom.

Burrows are also where groundhogs hibernate. Hibernation is kind of like a deep sleep that some animals settle into in order to make it through the winter.

When groundhogs hibernate, their heart rate slow down from about 80 beats a minute to as few as 4 or 5 beats a minute, and during hibernation, a groundhog's body temperature changes, too.

Groundhogs normally have a body temperature that's pretty close to yours: about 37ºC or 98.6ºF. But when they're hibernating, their body temperature drops all the way down to about 5ºC or 41ºF.

A slower heartbeat and a low body temperature help the groundhog to save energy through the cold winter when they aren't eating.

And to get ready for their long hibernation, groundhogs spend most of the fall eating as much as they can. This helps them build up a lot of fat in their bodies. They can then use this fat for energy while they hibernate because they won't come out of their burrows even to eat from October to March.

And that means if old Punxsutawney Phil is up and about on February 2nd to see his shadow, then he must have gotten up a little too early!


Thanks for joining us on SciShow Kids! Have you ever wondered why something happens or home something works? Let us know! Leave us a comment below or send us an email at kids@thescishow.com, and we'll see you next time.

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